School of Mechanical and Advanced Materials Engineering, Ulsan National Institute of Science and Technology (UNIST), UNIST-gil 50, Ulsan 689-805, Republic of Korea.
ACS Nano. 2012 Apr 24;6(4):2984-91. doi: 10.1021/nn300280q. Epub 2012 Mar 12.
We present an investigation of polymer light-emitting diodes (PLEDs) with a solution-processable graphene oxide (GO) interlayer. The GO layer with a wide band gap blocks electron transport from an emissive polymer to an ITO anode while reducing the exciton quenching between the GO and the active layer in place of poly(styrenesulfonate)-doped poly(3,4-ethylenedioxythiophene) (PEDOT:PSS). This GO interlayer maximizes hole-electron recombinations within the emissive layer, finally enhancing device performance and efficiency levels in PLEDs. It was found that the thickness of the GO layer is an important factor in device performance. PLEDs with a 4.3 nm thick GO interlayer are superior to both those with PEDOT:PSS layers as well as those with rGO, showing maximum luminance of 39 000 Cd/m(2), maximum luminous efficiencies of 19.1 Cd/A (at 6.8 V), and maximum power efficiency as high as 11.0 lm/W (at 4.4 V). This indicates that PLEDs with a GO layer show a 220% increase in their luminous efficiency and 280% increase in their power conversion efficiency compared to PLEDs with PEDOT:PSS.
我们研究了具有溶液处理氧化石墨烯（GO）层的聚合物发光二极管（PLED）。具有宽能隙的 GO 层阻止了从发射聚合物到 ITO 阳极的电子传输，同时减少了 GO 和活性层之间的激子猝灭，取代了聚（苯乙烯磺酸盐）掺杂的聚（3,4-亚乙基二氧噻吩）（PEDOT：PSS）。GO 层最大限度地提高了发射层中的空穴-电子复合，最终提高了 PLED 的器件性能和效率水平。结果发现，GO 层的厚度是器件性能的一个重要因素。具有 4.3nm 厚 GO 层的 PLED 优于具有 PEDOT：PSS 层的 PLED 以及具有还原氧化石墨烯（rGO）的 PLED，其最大亮度为 39000Cd/m2，最大亮度效率为 19.1Cd/A（在 6.8V 时），最大功率效率高达 11.0lm/W（在 4.4V 时）。这表明与具有 PEDOT：PSS 的 PLED 相比，具有 GO 层的 PLED 的亮度效率提高了 220%，功率转换效率提高了 280%。
